@Chris Collins
Loyd is correct about the temperature in space near earth as such. I can't find a source for a good figure near the earth, but cooling was a significant issue for Apollo 13. Substantial cooling will occur simply from radiation in space, so an area away from the heating support systems for any vehicle in space will cool substantially. What it this doesn't take into account is transport to and from the surface of the earth, and for that part of the journey both substantial insulation and cooling would be required. (Although I've never understood the desire to bring potentially deadly materials back to earth. Far better to study them in space where if something goes hideously wrong you can try to contain it, maybe even launch it into the sun.)
Oh, and the sun doesn't freeze because the gravitational energy of the sun keeps it in a plasma state in which nuclear fusion occurs, which also adds to the temperature of the sun.
Yeah, I was an astro major a long long time ago, although I eventually gave it up because arithmetic and I don't get along.
One last note, conduction via metal is the most efficient heat transfer mechanism. Which means that a box attached to an array of metal fins that radiate the heat away would actually be the fastest means to transfer heat away in space.